Topographical EEG analysis of rolandic spikes

We performed topographic EEG investigation with instant voltage mapping in 57 patients with a Rolandic spike focus including 35 patients with benign Rolandic epilepsy. A pronounced maximal negativity of "Rolandic" spikes could be demonstrated over central or mid-temporal electrodes, with a spread to parietal or upper frontal areas with a dipole formation (centrotemporal negativity, frontal positivity) and involvement of midline. There was a moderate correlation between spike amplitude or duration with spread to adjacent areas. No other focal abnormalities such as focal slowing could be revealed by visual or FFT EEG analysis. During light sleep spike activity was pronounced and often associated with generalized spike wave activity. Thus, a functional disturbance rather than a structural lesion can be assumed.